During the Games it was considered the best (and fastest) pool in the world and hosted the swimming, diving, synchronised swimming, as well as the finals of the water polo and the swimming leg of the pentathlon.
Since the games it has received over 100,000 visitors per month, with numbers rising to nearly 7000 per day during hot summer weekends and school holidays.
The centre is definitely not just for lap swimmers. From the website:
"The Sydney Olympic Park Aquatic Centre’s water wonderland includes five spas, sauna, steam room, river rapid ride, spray jets, spurting volcanos, water slide and bubble beach, surrounded by lush palm trees and colourful mosaics.
Professional supervision and luxurious heated water means you can play all day without a care in the world! You can take the challenge and conquer the large pool inflatable obstacle courses and the giant inflatable Coke water slide."
There is also a massage room, and a cafe to give you the energy you'll need to try everything out.
There is 4 hours of free parking available (don't forget to validate your ticket) and buses and trains also service the Olympic Park. Here is a good summary of your transport options.
Note that the lower leisure pool will be closed until Sunday 2 November 2008 for upgrades, however the upper leisure pool will still be open. If you want the full experience it's probably best to wait until next weekend, however it looks like upgrades of some sort be underway for a while.
Why? A really fun way to cool off on a hot summer day.